Fixed combination therapy of hypertension: focus on valsartan/hydrochlorothiazide combination (Diovan/HCT).

Hypertension is a major risk factor for cardiovascular morbidity and mortality. Monotherapy of hypertension is often ineffective, since it controls approximately 50% of the blood pressure of hypertensive patients. For lowering blood pressure to less than 140/90 mmHg (or <130/80 mmHg among people with diabetes or chronic renal disease) according to JNC-7 guidelines, combination therapy of two or more drugs is often necessary. The combination of a diuretic with an angiotensin-converting enzyme inhibitor (ACEI) or an angiotensin receptor blocker (ARB) is effective and provides the additional benefit of blocking the effects of angiotensin II, which is responsible for cardiovascular remodeling and its complications. ARBs may have an advantage over the ACEIs because they block the action of all angiotensin II directly, whereas ACEIs are ineffective in blocking angiotensin II generated by nonclassical ACE pathways. Valsartan (Diovan, Novartis) is one of the seven currently approved ARBs in the USA for the treatment of hypertension, and it has been shown to be very effective in controlling blood pressure given once-daily in doses of 80-160 or 320 mg. Its fixed combination with hydrochlorothiazide (HCT) is even more effective in controlling blood pressure in 70% of the cases. The most commonly used combinations are valsartan/HCT (Diovan/HCT), 80/12.5 and 160/12.5 mg given once-daily.